Magnetic releasable locking mechanism for cord reels

ABSTRACT

A spring-wound rotatable cord reel having a fixed magnetized ratchet and a pawl of magnetically attractable material pivotally secured to and rotatable with the reel, the pawl lockingly engaging the ratchet when the reel rotates in a cord-winding direction at a relatively slow rate and orbiting around the ratchet when the reel rotates in a cord-unwinding or payout direction at a faster rate, so that the cord can be rapidly pulled out to the desired length and then gently released to latch or lock it in this position and thereafter, if desired, pulled out again and rapidly released until the entire cord is retracted and wound on the reel.

United States Patent Inventor Appl. v\' ov Filed Patented Assignee MAGNETIC RELEASABLE LOCKING MECHANISM FOR CORD REELS 14 Claims, 5 Drawing Figs.

11.8. CI 242/ 107.7 Int. Cl B65h 75/48 Field olSearch 242/18,47,

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'IIIIIIIIIIIIIIII References Cited Primary Examiner-Stanley N. Gilreath Assistant E.\'aminerwerner H. Schroeder Arlorney- McClure, Weiser and Millman ABSTRACT: A spring-wound rotatable cord reel having a fixed magnetized ratchet and a pawl of magnetically attractable material pivotally secured to and rotatable with the reel, the pawl lockingly engaging the ratchet when the reel rotates in a cord-winding direction at a relatively slow rate and orbiting around the ratchetwhen the reel rotates in a cord-unwinding or payout direction at a faster rate, so that the cord can be rapidly pulled out to the desired length and then gently released to latch or lock it in this position and thereafter, if desired, pulled out again and rapidly released until the entire cord is retracted and wound on the reel.

PATENIEU am: 3 m1 SHEET 2 BF 2 2,314,177 have the disadvantage that they arerinoperable when the axis of rotation of theisheave. thereofi is vertical.

Cord-reels with springfactuated-pawl type sheave-latching,

20- 2,391,840 and 2,5 30,733 have-thedisadvantageof being;more-- difficult to operate and requiringthat theoperator;h'ear-,-the-- clicking sound of the pawlagainstthe ratchet-inorderto' means as described, for. exampleJn U.S. Pat.. Nos. 2,375,9-l 7;

release the cord just at the right moment for its spring woundretraction. Still other conventional; latchingreels= involve mechanisms of undue complexity and, multiplicityotl parts in,- herently too expensive, and not as durable cit-reliable.-

Theprimary object of this invention is toprovide a cord reel.

having means to urge the cordtintoiits wouncLor stored posi tion which overcomes the disadvantages'oflthe,.:aforemenr= tioned conventional .reels byemployingla. fixed-magnetic ratchet and a pawl. rotatable with thereel-and orbiting around the ratchet whereby as thecord is pulled' outtothedesiredx length the pawl orbits theratchet andwhen the cordis gently released and the reel rotates relatively-slowly ina reverseorcord-winding direction, the pawl will; lockingly; engage the ratchet at a position to retain the cordatthe desired extended or payout. length;,and when the cord is quicklyreleased and! the reel rotates rapidly in the cord-winding direction, the pawl. again orbits the ratchet until the entire lengthvofithe cord.is-

retracted to its original nonextendedposition.

Another object of the invention is to, provide a cord reel of J the character described in whieb the. magnetized ratchetisin.

the form of a notched disc and a meansisprovidedwhich extends from the periphery thereofadjacentweach,notch'whiche performs the dual functionofleading thenpawl into positive' locking engagement with the: notch when the reelrotates rela-.:

tively slowly in the cord-windingdirection. and of engaging the:

pawl. but urging it past the notchwhen thereelrotates relative-.

ly. quickly in both the cord unwinding-rand. cord-winding.

direction, thus simplifying the'operation. of pulling-outth'e cord to the desired lengthand releasing it'to-effect eitherlocking of the cord at saidpaid out length or allowing it to retract completely to its stored positions;

with means urging the cord to. its wound-orgstored-position-in; which the ratchet is in the form of apermanently magnetized nonrotatable disc with a plurality otlwspaced notches through;-

its periphery, humps extending radiallyifrom the periphery between the notches, anorbiting: pawl of magnetically attractable-material pivoted to-andt rotatable with the reel having, a protuberance complementary: to- :eachmotc'hiand-l .stop means causing the protuberance-to contact-the humps.

whereby relatively rapid rotationofi thereel will-create-a cen,-

trifugal force overcoming the-magnetic attraction betweenthe ratchet and pawl so that thelatter will-orbit the :ratchetas its 1' protuberance wipes the humpswithout engagement intany notchgand whereby upon relatively slow rotation votl'the reelin the cord-winding direction, the magnetic attraction wilt-over come the centrifugal forceand thehumps willacttopositively leadthe pawl. protuberance to dropeinto anearby 'notch.

A further object of the invention is" to=provide azcord; reel oi? the character described which is 'relativelyeasy to-manufae tureand-assemble, inexpensive and-easy-tooperate.

55 Another object of the lnventlonais toprovlde-a cord: reell:

2. Theseandiother. objectsrofithesinvention will become more apparent as the following'description proceedsin conjunction with the accompanyingdrawings, wherein:

FIG. lis-a si'deeIeVationaLvievv of the cord. reel embodying theinvention; v

FIG.- 2' is a. sectional view, somewhat enlarged, taken on the lineZK -ZQEHG; 1; g 1

FIG.- 3 isasectional: view-taken:ontheliheG-S of FIG;- 2 and-- illustratingathe'- position of the pawl in' locking, engagement with the: magnetic ratchet when: the reelt rotates relatijyelyslowly'in thezwinding direction;

Flfi. 4isa view similar to: FIG; 3 05 'a modified formof the invention wshowinggth'e position; of the pawl against the mags netioratchet-whemthe reelrotates relatively slowly; and

FIG-. 5 is a viewsimilar to FIG: 4 illustrating. the position of v the pawl relativeatoth'e ratchet when the-reel rotates relatively rapidllyiwithl centrifugal forceurging: the-pawl: away from the ratchet.

The presentinvention-is applicable to-b'oth electric and nonele'ctric cord-reels of the-type-whichgenerally-include a stationary arbor, a word-storage sheave rotatably mounted I thereon. and. havinga. hollow cylindricaldrumlike hub to or within-which'the-inner end of the cord is. anchored and onto which-v the cord is WQUIldytWO generally parallel spaced-apart flanges extendingradiallyoutwardly from the hub'fo'r laterally? confiningthe-cordon-the'hub, and means urging the cord into the storedorwoundpositiomsuch asa'flat helicalcord-winding spring fwithin'the'hubg'having its inner end anchored'to'the arbor anditsouterend anchoredtothe hub.

Thegenerab. construction and arrangement" of "partsof such electric'cord'reels: are disclosedin U-'.S.- Pat. Nos. 2,3759 17;

2,3915840 and.2',948,9 l '3 which-are herein incorporated-by reference. The nonelectric cord-i'eel's 'omit the electriccoreneticrele'asablelocking or latching mechanism for cord'reels equipped: with a .meanszurgin'g-thescord into" its storedor wound position, only those. parts essential tov the invention are shown in the. accompanyingdrawings.

Indicated generaliyatvlf is: a stationary arbor and a stationary bracket or support-12 thereforrwhilethesupportl2 is shown as beingza generally U-shaped bracket having opposite legsv l3 and-14 to-whi'ch theopposite ends of the arbor-11' are" secured',",tlte support can'be of any othersuitable form or character'ifidesired. The outer reduced ends-of the-arbor 1 1: are keyedby any suitable. means to the bracket or support 12 by'a pair of oppositelflats on the arbor and'- by correspondingly shaped holestin thez bracketandthere retained by' a headedscrew 15; threaded into an axialhole in' the-arbor: The red in cludes a sheave which isrotatably' mounted on th'e=arborlI=' and. includes :a hub- 16 andra pair of spaced apart'cord-confining flanges:-l8"extending: radially outward-from the'hub thereof.

and: inner flatradialLwallsEor bottomswith central arborreceivingzholes therethrouglr, their inner radial' walls being ar-- ranged back-to-back. and secured: to each. other byanysuitabl'emeans; one of which. cuplikehub portions constitutes the electrical-chamber'im which the electric-cord is mounted and .the-otheraspring-chamber-iniwhicha flathelical cord-winding spring is operatively mounted; I

sheave. is preferablyformed integrally with a. corresponding cuplilte hub portionuil'he flange-.18 onthespring side ofthe v sheaveis-preferabl'y formed. separately from the correspond ing. cuplike hub. portion,.- and-extendsmot' only radially -out-' iwardlytromthe cylindrical awall=of said liub portion. but'also extends radially inwardly therefrom andthus-encloses the cord-winding-spring within such hub -portion. The' spring withinzsuehthubtportion (not-shownfiahasan innerend which is anchoredinzthe slot: 19 0f the arbor and an outerend-which. is ':securcdto thehub-portion. A cord 205s provided who'se inner within 'thehub; thetelectric collector rings and thebrus'hes. Accordingly, sincethe: instanrinvention-is directed to a mag- The-hub 16 of the sheave. is preferablyformed of two shal low cuplikehalves having-generally cylindricaltout'er sidewalls Th'eicordi-confiriing. flangerlfi onthe-electri'cal side of the end passes through a suitable aperture in the hub and is anchored thereto in the manner disclosed in U.S. Pat. No. 2,948,913, the spring or other means normally acting to retract the cord and wind it around the hub as indicated bythe arrow 22 in FIG. 5, the reverse or unwinding direction of the reel for cord extension being shown by the arrow 24 in F IG. 5. The cord may be provided with a conventional electrical plug 26 at its outer end for engagement in a suitable outlet socket. g

The present invention comprises a magnetic pawl and ratchet means to permit one readily and easily to pull out the cord and then gently, release it to obtain a desired length of payout or to rapidly release the cord for total retraction and winding about the hub back to its initial position.

The pawl is in the form of a generally arcuate finger 28 which is pivoted adjacent one of its ends as at 30 to one of the flanges 18 around an axis substantially parallel to the axis 32 of rotation of the sheave. Adjacent its free end and extending inwardly towards the arbor, the pawl has a protuberance 34 having opposed surfaces 36 and 38.

The pivotal attachment of the pawl to the sheave for rotation therewith is effected, for example, by first mounting the pawl on a tubular stepped rivet 40. Thereafter the rivet 40 is extended through a hole in a boss 42 provided in the flange l8 and there peened. A cap member 44 is then riveted to the outer end of the rivet 42 and a similar diametrically opposed rivet 46. v

The cap member 44 has a generally cylindrical flange 48, the edge of which bears against the sheave flange 18. The cap member 44 is also provided with a central inwardly offset annular portion 50, which prevents the axially outward displacement of the magnetic ratchet disc, without however restraining the free rotation of the cap member 44 or the flange l8 mounting the pawl about'the stationary arbor 11 as an axis. The flange 18 is also provided centrally thereof with a generally cylindrical inner annular flange 52 which serves to journal the sheave on the uninterrupted cylindrical portion of the arbor ll.

' The pawl 28 may be formed of iron or soft annealed steel,

such as cold-rolled steel or other equivalent ferrous material which can be magnetically attracted but which can not be permanently magnetized or which does not retain any significant magnetism'of its own, independently of the attractive magnetic field otherwise provided by another permanent magnetic source as will appear hereinafter. The ratchet is generally indicated at 54 and is in the'form of a magnetized disc fixedly mounted on or keyed to the arbor in any appropriate manner substantially axially therewith and is adapted to lockingly or releasably engage the pawl which orbits it as the reel rotates. Opening through the periphery 56 of the ratchet disc is a pair of diametrically opposed notches 58 each complementary to the protuberance 35 of the pawl, and therefore each notch includes opposed faces 60 and 62 equivalent to faces 36 and 28 respectively of the pawl protuberance.

In the modified form shown in FIGS. 4 and 5, periphery 56 of the ratchet disc is additionally provided on the side closely adjacent the angulated or locking face end of each notch with an outwardly or radially extending rounded hump 64 whose circumferential length is only a small portion of the distance between the notches.

The ratchet disc is magnetizedto provide a field extending radially outwardly from and uniformly its periphery towards the pawl. it may be magnetized, for example, by forming it of a single ply sheet of permanently magnetized hardened steel of Alnico or other material which has been permanently crossmagnetized so that its North pole will extend throughout one face thereof, or at least throughout its peripheral edge, and so that the South pole will extend throughout the other face or at least through its peripheral edge, thereby creating a uniform magnetic attraction of the pawl 28 throughout its peripheral edge.

The ratchet disc is preferably formed of soft or annealed steel, such as cold-rolled steel, and a washer 66 is interposed between the disc and the flange 18, which washer may be formed of a permanently cross-magnetized ferrous material, such as a rubber or rubberlike or other suitableplastic matrix through which permanently magnetizable ferrous particles, such as barium ferrite powder, are uniformlydis'tributed, and which is thereafter permanently cross-magnetized. Such permanently cross-magnetized disc is thus sandwiched between the steel pawl-mounting flange l8 and the steel ratchet disc, thereby forming a magnetic circuit through the flange 18 and the ratchet disc 54. This sandwich arrangement is superior to the one in which the magnetized disc is attached to a nonmagnetic support of flange 18, made of aluminum, plastic a or the like; for the pawl is in stronger area of magnetic flux in the sandwich construction, and hence reactsvmore readily than in the nonsandwich arrangement.

The cap member 44 which encloses the pawl 28 and the notched ratchet disc 54 may be made out of a nonmagnetic material such as aluminum, brass or the like, so as not to divert or dilute the magnetic field of the ratchet disc.

When the cord 20 is pulled out rapidly it causes the reel to rotate at a relatively high speed. The centrifugal force generated causes the pawl to pivot so that' its free end containing the protuberance 34 moves away from the ratchet disc 54. At a predetermined velocity of the reel, the centrifugal force generated exceeds the magnetic attraction of the stationary ratchet disc so that the pawl orbits the ratchet disc without engagement of the protuberance in any notch 58, or for that matter with the periphery 56 of the ratchet. The outward movement of the pawl when it orbits in the nonlatching operation is limited by the engagement of the edge of the pawl opposite its protuberance 34-with the annular flange 48 of the cap cover 44, or by the engagement of a rounded bump 68 against said annular flange 48.

When the reel is rotated at a relatively slow speed, the centrifugal force generated is not sufficient to to prevent magnetic capture of the pawl by the ratchet disc and hence the protuberance 35 of the pawl will be enabled to lockingly engage in the next oncoming notch. In the unwinding direction shown by arrow 24, the protuberance 68 will not lock or latch in the notch because if the protuberance does happen to fall into a notch the camming engagement of the corresponding faces 60 and 36 of the notch and protuberance respectively will force the protuberance out of the notch. Hence the cord can be pulled out at any speed to the desired length. However, in the winding direction shown by arrow 22, if it is relatively slow, as indicated hereinbefore, the protuberance 34 of the pawl can enter the next oncoming notch and latchingly engage therein, as shown in FIG. 3, because the coacting faces 62 and 38 of the notch and pawl protuberance respectively are noncamming.

In use, after the cord is pulled out to the desired length, if it is released gently by frictionally restraining its retraction or rewinding movement, the pawl protuberance will latchingly engage in the next oncoming notch and retain the cord in the desired extended length'thereof. When one wishes to effect complete retraction or storage of the cord on the sheave of the reel, he need merely pull out the cord briskly and then release it. The speed or rotation of the reel will be large enough to cause the pawl by the generated centrifugal force to orbit the ratchet disc e without having the protuberance 34 enter a notch until the cord is completely retracted.

With respect to the modified device of FIGS. 4 and 5, in the relatively rapid orbiting of the pawl around the ratchet disc the engagement of the rounded hump 68 against the annular flange 48 of the cover so confines the pawl that its protuberance 34 always wipes the high points 64 on the disc. Thus, when the reel rotates relatively rapidly, the wiping action of the humps 64 against the protuberance of the pawl apparently aids the generated centrifugal force in keeping the pawl protuberance from dropping into the ratchet notch. When the cord is pulled out, the pawl generally orbits slowly aroundthe fixed recapture and retain the pawl more firmly; and thus when'the reel rotates relatively slowly upon release of the cord in its cord-winding direction, the same humps tend to lead the. pawl protuberance into the next oncoming notch.

ltshould be understood that while the humps 64 onthe periphery of the ratchet disc are shown as discrete enlargements extending radially outwardly of the periphery, they may be formed of a gradual increase of the radiusof the disc from a particular locus on the peripheryup to a point adjacent the corner 70 of the rounded camming face 60 of the notch. Also,

although the ratchet disc is shown-as containing two notches.

58, one notch can also be employed'as well as three or more equally spaced around the periphery, as also can more than one pawl if desired.

While a preferred embodiment has here been shown and described, it will be understood that a skilled artisan may make variations without departing from the spirit of the invention.

The invention I claim is:

l. in a rotary cord reel including means urging the cord into a wound position, a fixed magnetized ratchet and a pawl of magnetically attractable material pivoted to said reel and rotatable therewith so that said pawl orbits said ratchet and lockingly engages said ratchet when said reel rotates at a relatively slow speed in a cord-winding direction and said pawl does not lockingly engage said ratchet when said reel rotates at a greater speed in either direction.

2. in a rotary cord reel including means urging the cord into a wound position, a fixed magnetized ratchet anda pawl of magnetically attractable material pivoted to said reel and' rotatable therewith so that said pawl orbits said ratchet .and'

lockingly engages said ratchet when said reel rotates at a rela tively slow speed in a cord-winding direction and said pawl does not lockingly engage said ratchet when said reel rotates 7. The combinationofclaim 5 wherein said notch includes camming face coacting with a similar face on said pawl protuberance to urge' said pawl protuberance out of said notch when a'pullis-exerted on the cord and a locking face in said notch coacting with a similar face on said pawl protuberance to lock said pawl protuberance in said notch when the cordis released. i

8. in a rotary cord reel including means urging the cord into the woundposition, a fixedly mounted ratchet disc including at least one notch in'its peripheral edge, a pivotally mounted orbiting pawl rotating with said reel and including a protuberance complementary to said notch, means creating a magnetic field drawing'said pawl towards said ratchet disc and means protruding from said peripheral edge of said ratchet disc, said magnetic field being of strength sufficient to hold said pawl protuberance against said peripheral edge of said disc when said reel rotates relatively slowly in the winding direction to allow said pawl protuberance to engage said notch, the magnetic field strength being insufficient to overcomethe centrifugal force urging said pawl away from said disc when said reel rotates more rapidly in either direction, said means protruding from said peripheral edge engaging said pawl protuberance performing the dual function of assisting in at a greater speed in either direction and a fixed arbor about which said reel rotates, said ratchet including adisc keyed .to

said arbor, a magnetizable metal plate carried by said reel-and a washer interposed between said disc and plate comprised of pennanently cross-magnetized particles in aplastic matrix.

3. The combination of claim 2 in which said .ratchetdisc includes at least one notch opening through its peripheral edge and said pawl includes a protuberance complementarythereto.

and engageable therein.

4. The combination of claim 3 and means protruding from said ratchet engageable with said pawl to aid in keeping said pawl protuberance out of said notch when reel rotates relatively rapidly and to lead said pawl protuberance into said notch when said reel rotates relatively slowly in the cord-winding direction.

keeping said pawl protuberance out of engagement with said notch when said reel rotates relatively rapidly and positively leading said pawl protuberance into said notch when said reel rotates relatively slowly in the winding direction wherein said ratchet .disc includes a pair of diametrically spaced notches and .said means protruding from said peripheral edge of said disc is a hump leading to said face opposite said locking face of said notch.

9. The combination of claim 5 and means limiting outward movementofsaid pawl as it orbits said ratchet disc so that said pawl protuberance engages said means protruding from said peripheral edge of said disc.

10; In a spring-powered rotary cord-reel including a cordwinding sheave havinga'hub and apair of spaced cord-confining flanges extending radially therefrom'with a cord having an inner end secured to said hub and adapted to be spring-wound thereon; a magnetic reel locking and release mechanism com- 5. The combination of claim 3 wherein said notch includes a v camming face adapted to expel a pawl-when the reel rotates in i one direction and a locking face adapted to retain a pawl when the reel rotates in an opposite direction.

6. in a rotary cord reel including meansurging the cord into the wound position, a fixedly mounted ratchet disc including at least one notch in its peripheral edge, a pivotally mounted orbiting pawl rotating with said reel and includinga protuberance complementary to said notch, means creating a magnetic field drawing said pawl towardssaid ratchet-disc andmeans protruding from said peripheral'edge of said ratchet disc, said magnetic field being of strength sufficient to hold said pawl protuberance against said. peripheral edge of said disc when said reel rotates relatively slowly in the winding direction to allow said pawl protuberance toengage said notch,-the magnetic field strength being insufficient to overcome the centrifugal force urging said pawl'away from said disc when said reel rotates more rapidly in either direction, v

said means protruding from said peripheral edge engaging said pawl protuberance performing the dual function of assisting-in keeping said pawl protuberance out of engagement with said notch when said reel rotates relativelyrapidly and positively leading said pawl protuberance into said notch when. said reel rotates relatively slowly in the windingdirection.

prising a ratchet disc nonrotatably-mounted adjacent said sheave-and generally coaxialtherewith, at least one notch openingthrough the peripheral edge of said ratchet disc, an

orbitinggpawl pivoted to said sheave and including a protube rancecomplementary to said notch, means creating a magnetic field acting to draw said pawl towards said ratchet disc of such magnitude that when said sheave is caused to rotate relatively rapidly the centrifugal force generated is greater than the magnetic field strength so that said pawl is urged outwardlyof saiddisc and when said sheave is caused torotate relatively slowly, said'magnetic field strength will capture said pawl and allow its protuberance to enter said notch and be lockingly retained therein, and means limiting the pivotal movement of said pawl outwardly away from said ratchet disc so that said protuberance of said pawl will contact the periphery of the ratchet disc during relatively slow orbiting of said pawl around said ratchet.

11. in a spring-powered rotary cord-reel including a cord- 1.winding sheavehavinga hub and a pair'of spaced cord-confining=flanges extend-ing'radially'therefrom with a cord having an inner endsecured to saidhub and adapted to be spring-wound thereon; a magnetic reel locking andrelease mechanism comprising a ratchet disc nonrotatably mounted adjacent said sheave and generally coaxial therewith, at least one notch opening'through the peripheral edge of said ratchet disc, an orbiting pawl pivotedto said sheave and including a protuberance complementary to -said 'notch, means creating a magnetic fieldacting todraw said pawl-towards-saidratchet disc of such magnitude-that when said sheave is caused to rotate relatively rapidlythe centrifugal force generated is greater than the magnetic field strength so that-said pawl is urged outwardly of-said disc and when said sheave is caused to rotate relatively slowly, said magnetic fieldstrength will capture-said pawl-and allow its protuberance to enter said notch and be lockingly retained therein, and means limiting the pivotal movement of said pawl outwardly away from said ratchet disc so that said protuberance of said pawl will contact-the periphery of the ratchet disc during relatively slow orbiting of said pawl around said ratchet wherein said pawl limiting means includes a cover for said ratchet disc and pawl including an annular wall, a portion of the edge of said pawl opposite its protuberance being adapted to engage said annular wall when said pawl orbits said ratchet relatively rapidly.

12. The combination of claim 11 wherein said notch includes opposed circumferentially spaced faces, one of which is adapted to cammingly engage a corresponding face of said pawl protuberance to permit release of said protuberance form said notch when a pull is exerted on the cord to unwind it from the sheave, the other face of which coacts with a corresponding face of said pawl protuberance to lock said protuberance in said notch when the cord is released and the sheave rotates relatively slowly in a winding direction.

13. The combination of claim 12 wherein said ratchet disc includes a pair of diametrically opposed notches.

14. The combination of claim 10 wherein said ratchet disc and one of said cord-confining flanges is made of a magnetizable metal and said means creating the magnetic field includes a washer comprised of permanently cross-magnetized particles distributed in a plastic matrix and interposed between said ratchet disc and said one cord-confining flange. 

1. In a rotary cord reel including means urging the cord into a wound position, a fixed magnetized ratchet and a pawl of magnetically attractable material pivoted to said reel and rotatable therewith so that said pawl orbits said ratchet and lockingly engages said ratchet when said reel rotates at a relatively slow speed in a cord-winding direction and said pawl does not lockingly engage said ratchet when said reel rotates at a greater speed in either direction.
 2. In a rotary cord reel including means urging the cord into a wound position, a fixed magnetized ratchet and a pawl of magnetically attractable material pivoted to said reel and rotatable therewith so that said pawl orbits said ratchet and lockingly engages said ratchet when said reel rotates at a relatively slow speed in a cord-winding direction and said pawl does not lockingly engage said ratChet when said reel rotates at a greater speed in either direction and a fixed arbor about which said reel rotates, said ratchet including a disc keyed to said arbor, a magnetizable metal plate carried by said reel and a washer interposed between said disc and plate comprised of permanently cross-magnetized particles in a plastic matrix.
 3. The combination of claim 2 in which said ratchet disc includes at least one notch opening through its peripheral edge and said pawl includes a protuberance complementary thereto and engageable therein.
 4. The combination of claim 3 and means protruding from said ratchet engageable with said pawl to aid in keeping said pawl protuberance out of said notch when reel rotates relatively rapidly and to lead said pawl protuberance into said notch when said reel rotates relatively slowly in the cord-winding direction.
 5. The combination of claim 3 wherein said notch includes a camming face adapted to expel a pawl when the reel rotates in one direction and a locking face adapted to retain a pawl when the reel rotates in an opposite direction.
 6. In a rotary cord reel including means urging the cord into the wound position, a fixedly mounted ratchet disc including at least one notch in its peripheral edge, a pivotally mounted orbiting pawl rotating with said reel and including a protuberance complementary to said notch, means creating a magnetic field drawing said pawl towards said ratchet disc and means protruding from said peripheral edge of said ratchet disc, said magnetic field being of strength sufficient to hold said pawl protuberance against said peripheral edge of said disc when said reel rotates relatively slowly in the winding direction to allow said pawl protuberance to engage said notch, the magnetic field strength being insufficient to overcome the centrifugal force urging said pawl away from said disc when said reel rotates more rapidly in either direction, said means protruding from said peripheral edge engaging said pawl protuberance performing the dual function of assisting in keeping said pawl protuberance out of engagement with said notch when said reel rotates relatively rapidly and positively leading said pawl protuberance into said notch when said reel rotates relatively slowly in the winding direction.
 7. The combination of claim 5 wherein said notch includes a camming face coacting with a similar face on said pawl protuberance to urge said pawl protuberance out of said notch when a pull is exerted on the cord and a locking face in said notch coacting with a similar face on said pawl protuberance to lock said pawl protuberance in said notch when the cord is released.
 8. In a rotary cord reel including means urging the cord into the wound position, a fixedly mounted ratchet disc including at least one notch in its peripheral edge, a pivotally mounted orbiting pawl rotating with said reel and including a protuberance complementary to said notch, means creating a magnetic field drawing said pawl towards said ratchet disc and means protruding from said peripheral edge of said ratchet disc, said magnetic field being of strength sufficient to hold said pawl protuberance against said peripheral edge of said disc when said reel rotates relatively slowly in the winding direction to allow said pawl protuberance to engage said notch, the magnetic field strength being insufficient to overcome the centrifugal force urging said pawl away from said disc when said reel rotates more rapidly in either direction, said means protruding from said peripheral edge engaging said pawl protuberance performing the dual function of assisting in keeping said pawl protuberance out of engagement with said notch when said reel rotates relatively rapidly and positively leading said pawl protuberance into said notch when said reel rotates relatively slowly in the winding direction wherein said ratchet disc includes a pair of diametrically spaced notches and said means protruding from said peripheral edge of said disc is a hump leading to saiD face opposite said locking face of said notch.
 9. The combination of claim 5 and means limiting outward movement of said pawl as it orbits said ratchet disc so that said pawl protuberance engages said means protruding from said peripheral edge of said disc.
 10. In a spring-powered rotary cord-reel including a cord-winding sheave having a hub and a pair of spaced cord-confining flanges extending radially therefrom with a cord having an inner end secured to said hub and adapted to be spring-wound thereon; a magnetic reel locking and release mechanism comprising a ratchet disc nonrotatably mounted adjacent said sheave and generally coaxial therewith, at least one notch opening through the peripheral edge of said ratchet disc, an orbiting pawl pivoted to said sheave and including a protuberance complementary to said notch, means creating a magnetic field acting to draw said pawl towards said ratchet disc of such magnitude that when said sheave is caused to rotate relatively rapidly the centrifugal force generated is greater than the magnetic field strength so that said pawl is urged outwardly of said disc and when said sheave is caused to rotate relatively slowly, said magnetic field strength will capture said pawl and allow its protuberance to enter said notch and be lockingly retained therein, and means limiting the pivotal movement of said pawl outwardly away from said ratchet disc so that said protuberance of said pawl will contact the periphery of the ratchet disc during relatively slow orbiting of said pawl around said ratchet.
 11. In a spring-powered rotary cord-reel including a cord-winding sheave having a hub and a pair of spaced cord-confining flanges extending radially therefrom with a cord having an inner end secured to said hub and adapted to be spring-wound thereon; a magnetic reel locking and release mechanism comprising a ratchet disc nonrotatably mounted adjacent said sheave and generally coaxial therewith, at least one notch opening through the peripheral edge of said ratchet disc, an orbiting pawl pivoted to said sheave and including a protuberance complementary to said notch, means creating a magnetic field acting to draw said pawl towards said ratchet disc of such magnitude that when said sheave is caused to rotate relatively rapidly the centrifugal force generated is greater than the magnetic field strength so that said pawl is urged outwardly of said disc and when said sheave is caused to rotate relatively slowly, said magnetic field strength will capture said pawl and allow its protuberance to enter said notch and be lockingly retained therein, and means limiting the pivotal movement of said pawl outwardly away from said ratchet disc so that said protuberance of said pawl will contact the periphery of the ratchet disc during relatively slow orbiting of said pawl around said ratchet wherein said pawl limiting means includes a cover for said ratchet disc and pawl including an annular wall, a portion of the edge of said pawl opposite its protuberance being adapted to engage said annular wall when said pawl orbits said ratchet relatively rapidly.
 12. The combination of claim 11 wherein said notch includes opposed circumferentially spaced faces, one of which is adapted to cammingly engage a corresponding face of said pawl protuberance to permit release of said protuberance form said notch when a pull is exerted on the cord to unwind it from the sheave, the other face of which coacts with a corresponding face of said pawl protuberance to lock said protuberance in said notch when the cord is released and the sheave rotates relatively slowly in a winding direction.
 13. The combination of claim 12 wherein said ratchet disc includes a pair of diametrically opposed notches.
 14. The combination of claim 10 wherein said ratchet disc and one of said cord-confining flanges is made of a magnetizable metal and said means creating the magnetic field includes a washer comprised of permanently cross-magnetized particles distributed in a plastic matRix and interposed between said ratchet disc and said one cord-confining flange. 